Flexible link harrow



Nov. 3, 1964 w. D. HOFER 3,155,170

United States Patent O 3155170 FLEXTBLE LENK HARRGW Waler Um'id Hofes,Brecke, Aberia, Canaa, assigner cf ene-fourth t Lawrenee Benjamin Levineand ihreefeuxths to Garth Alphonse Tuseeit beh e Tzincher Creek,Aiberta, Canada Substued er abaneiene appleatien Sei. N0. 48,316, Aug.8, 1960. This applieaiien 3uly 31, 1963, Sei. N0.

Tl1is invention relates to harrows for soils eultivating and hasreference to a flexible assembly in which a series of harrow units areconnected. t0 move vertically and horizontally in relation L0 each otherin traveling over the ground.

In the art to Whieh the invention relates harrows are more usually madeup of elements forming a complete unit lacking flexibility in travelingover the land, and in which damaged arts are n0t readily replaceable.

The present device is designed to efiect improvemmts in seil cultivatingharrows of this character by forming the harrow of a series of squareunits that are pivotally connected together at the corners to beflexible horizontally and vertically, and in whieh the units are readilyreplaceable by the rernoval of connecting pins.

The units ean be assembled for travel hitched to a draw bar that lies atright angles to the travel 015 the harrow, or With the draw bar inclinedas it would be if attached behind a one-Way disk.

The two way flexibility of the harrow is efiective for self-cleaning,With little Chance of rocks loclging in the units, and for following thecontours of the land.

Other features and advantages of the invention will become apparent byreference to the accornpanying description taken in conjunction with thedrawings.

In the drawings, illustrating a preferred embodiment of the invention,

FIG. 1 is a plan view of a harrow in accorclance With my invention,shown With parts of the harrow removed and the teeth largely omitted.

FIG. 2 is a plan view of a series of connected harrow units,illustrating attachment of the units to a draw bar disposed at an angleto the direction of travel of the harrow, as when used With a one-Waydisk, and shown with the teeth omitted.

FIG. 3 shows a side view of a fragment of a harrow unit taken from theinside and illustrating attachment of a tooth.

Having reference to the drawings, the harrow is made up of a series ofsquare unit frames l, each having truncated corners 2 from. whichintegral hinge lugs 5 projeet outward and by whieh the frames may bepivotally connected to adjoining units and to the draw bar by pins 4engageable in openings, as at 6 in FIGURE 3, in the lugs. These lugs areattached t0 the corners 2 slightly ofl center to permit overlapping ofthe lugs of connected frames, and the pins would be held in the lugs,secured as by cotter pins or other suitable means.

T0 these sqnare frames are attached teeth 7, welded thereto and arrangedas desired both as to the number .Paented Nov. 3, 1964 of teeth per unitand the arrangement of teeth to provide an overall pattern. The teethare attached projecting at right angles to the unit fran1es With theprojecting ends of unequal length, as shown in FIGURE 3, so that byreversing the harrow diiferent harrowing depths are obtained. Preferablythe teeth projeet three inches in one direction and five inches in theother.

The units are attael1ed to a draw bar 8 with hiteh 9 by flat ironclevises 10 attaching to the draw bar by bolts 11 and to the unit lugsby pins 12.

A harrow section is formed as shown in FIGURE l, that is With sixsquares to the section, but when the harrow is set up for travel behinda one-way disk the arrangement of the squares would be as shown in FIG-URE 2. A unit may be removed from a seetion by taking out the connectingpins and the unit replaced by a fresh one.

Perferably there are four teeth in each square, arranged as shown inFIGURE l, with the upper tooth to the immediate left of the coupling.Each tooth in turn is similarly placed in relation to the coupling butthe spacing of the teeth from the coupling varies so that in a pair cfsquares attached in following relation the one from the other the teethof the two squaxes Would be spaced uniformly so that the eight teeth ofthe two squares would have a spacing of two inches apart relative to theline of. travel cf the section, as shown by the dashed lines.

In FIGURE 2 a hitch for use With a one-way dise is shown in which theclevises 10 pivotally attach by couplings 15 to the draw bar 8, and thedraw bar is connected by links 14 to the dise frame eross bar 13.

What I claim and Wish to secure by Letters Patent A harrow assembly forattachment in following relation to a draw bar, said assembly comprisinga series of square unit frarnes eaeh having its corners truncated and a111g fixed to each truneated corner oif center by whieh lugs of thecorners of adjoining frames may everlap, said lugs having pin reeeivingopenings, pins engageable in said openings for eonnection of unit framestogether and to the drawbar, said draw bar having clevises to which lugsof the frarnes are attachable, and teeth fixed to the sides of the unitframes arranged in a pattern common to all units with one tooth to eachside of a frame With the teeth cf each frame so spaced differently fromthe frame corners (disregarding said truncation) the frarnes may beconnected for a set of teeth in any one frame to travel in the intervalsbetween the the soll cultivated by teeth of frames aligned in advance orto the rear thereof.

Refe1renees Citeall by the Examiner UNITED STATES PATENTS 181,660 8/76Flower 172-623 FOREIGN PATENTS 1025458 4/53 France.

T. GRAHAM CRAVER, Primary Examiner.

